210 



METABOLISM AND PHYSIOLOGY 



the figure that the efficiency is slightly lowered in the presence of 

 MPM as compared to untreated chromatophores. In the systems (c) 

 and (d), where reactions of cytochromes of b and c types are inhibited 



REL. ACT. 



4 6 8 



Klux + 88A Filter 



10 



12 



Fig. 7. Comparison of phosphorylative systems at different light in- 

 tensities. Curves indicate ratios of phosphorylation rates. A: MPM- 

 catalyzcd phosphorylation/normal phosphorylation. B: phosphorylation 

 of MPM-HOQNO system/MPM-phosphorylation. C: phosphorylation of 

 MPM-antimycin A -system/MPM-phosphorylation. Concentrations of 

 reagents are the same as in Fig. 6. Temperature 24°C. 



and the flow of electrons is bypassed by MPM, the efficiencies are 

 about half of the original value. This means that one of the phosphory- 

 lating sites is located close to the oxidation- reduction site of cyto- 

 chromes h and c, and bypassing this site with MPM reduces the 



